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R Buller

Publications and source records attributed to R Buller.

At least 19 recordsLinked to original sources

Center differences and cross-national invariance in help-seeking for panic disorder. A report from the cross-national collaborative panic study.

Help-seeking behaviour for treatment of panic disorder was investigated in the sample of the Cross-National Collaborative Panic Study Second Phase. A total of 1168 patients were entered into this trial in 14 countries. Although there were significant center differences in prior treatment and utilization of health services there were also similarities. Treatment had been provided mainly by general practitioners. Drug treatment consisted mostly of prescription of classical tranquilizers and had a longer duration than treatment by psychotherapy. Patients with agoraphobic avoidance, past major depression and longer duration of illness used medical and psychiatric treatment facilities more intensely. Older and more severely disabled subjects were more frequently treated by medical health care providers and were more likely to receive psychotropic drugs. The results indicate that general practitioners carry an important load in the treatment of panic disorders but may need more information about recent development in pharmacotherapy for this condition.

Adult

Differentiation between major and minor depression.

Though the concept of Major Depression was generated by clinicians using depressed inpatients as models, a polydiagnostic study in 600 psychiatric inpatients with heterogenous psychological disturbances revealed that all six competing operational definitions of Major Depression (including DSM-III-R and ICD-10) were too restrictive to serve as a general concept of depression. Another polydiagnostic study in 500 primary care outpatients showed that more than two-thirds of all non-chronic depressed cases were below the severity threshold of Major Depression: these patients are classified as Depression Not Otherwise Specified (NOS) by DSM-III-R. Loosening of the over-restrictive time criteria would broaden the concept of Major Depression so as to meet the requirements of a general concept of depression, while the definition of Minor Depression below the threshold of Major Depression would add to a reduction of cases of NOS Depression by more than 80%. For the evaluation of antidepressant drugs in outpatient samples, we propose that patients with these modified definitions of Major and Minor Depression be included, provided they meet a minimum severity criterion of 13 or more points on the Hamilton Depression Scale; four-fifths of the modified Major Depression group and one-third of the Minor Depression group do in fact meet this criterion.

Depression

Pretreatment anxiety level as differential predictor in outpatients with panic disorder.

The pretreatment anxiety level is supposed to be a very important unspecific treatment factor. Main purpose of this study is to test whether the patients' pretreatment anxiety level is a general or a specific predictor of treatment response and whether mildly, moderately, and severely anxious patients can be differentially characterized by other diagnostic and clinical variables. 103 patients (37 males, 66 females; mean +/- sd age 35.6 +/- 9.5 years), a subsample of the Second Phase of the Cross-National Collaborative Panic Study, were included in the present study. A high positive correlation of initial anxiousness with the number of panic attacks at the end of treatment was found, moreover high positive correlations with most other baseline assessments. Initially severely anxious patients are the severest ill patients with the least treatment response, and that in all treatment groups. The pretreatment anxiety level predicts the number of panic attacks as well as the degree of avoidance behavior in both drug groups, whereas it predicts anticipatory anxiety intensity in the placebo group.

Adult

The significance of peritoneal cytology in stage IB cervical cancer.

OBJECTIVE: The purpose of this study was to determine the incidence of positive peritoneal cytology and to evaluate its usefulness in the management of patients with early-stage cervical cancer. METHODS: Peritoneal cytology was studied in 273 women undergoing primary surgical exploration for International Federation of Gynecology and Obstetrics stage IB cancer of the cervix. Charts were reviewed retrospectively for clinicopathologic data concerning tumor size, cell type, lymph node status, and outcome. RESULTS: Cytology was positive in four women, three of whom had enlarged pelvic or para-aortic lymph nodes or intraperitoneal disease. There was no association between tumor histology or tumor size and peritoneal cytology. CONCLUSION: The incidence of positive peritoneal cytology in early-stage cervical cancer is low, and the prognostic significance of positive cytology is overshadowed by other risk factors more obvious at surgery. The routine collection of cytologic specimens at laparotomy should be abandoned in this setting.

Female

Chronology of panic and avoidance, age of onset in panic disorder, and prediction of treatment response. A report from the Cross-National Collaborative Panic Study.

The relevance of the chronology between panic disorder and avoidance behavior and of an early, medium or late onset of panic disorder was tested. Groups from the sample of the cross-national collaborative panic study (CNCPS) were compared for differences in basic characteristics and for the ability to predict treatment response. Patients who developed avoidance behavior before the full syndrome of panic disorder had less often a full agoraphobia but were not different in their response to treatment. Patients with an early onset of panic disorder suffered more often from agoraphobia. The treatment response was similar in the groups with early, medium or late onset of panic disorder. Neither the chronology between panic disorder and avoidance behavior nor the age of onset of panic disorder predicted outcome in short-term treatment with alprazolam or imipramine.

Adult

Subtyping panic disorder by major depression and avoidance behaviour and the response to active treatment.

In order to establish the clinical validity of currently used ways of subtyping panic disorder the predictive power of associated current avoidance behaviour and (secondary) major depression for the response to active treatment (alprazolam, imipramine) was tested. The analysis was based on the data from the Cross-National-Collaborative-Panic-Study. Limited support for validity evidenced by predicting drug response was found for grading panic disorder by the severity of avoidance behaviour; patients with panic attacks and agoraphobia are more responsive to imipramine (compared with alprazolam) when using the reduction of the total number of panic attacks (or of spontaneous panic attacks) as the outcome criterion; patients without any avoidance behaviour did better with alprazolam (compared with imipramine).

Adult

Avoidance behaviour: a predictor of the efficacy of pharmacotherapy in panic disorder?

The impact of the avoidance behaviour on the psychopharmacological treatment of panic disorder was explored in the Cross National Collaborative Panic Study (n = 1134 patients); in this double blind randomized trial alprazolam, imipramine and placebo were compared during an 8-week treatment period. Patients with extensive avoidance behaviour (agoraphobia) had the most profit from the active drugs. Counter expectancy these specific drug effects were most pronounced in avoidance behaviour. Active drugs (in particular imipramine) were especially more effective than placebo if the patients presented with associated avoidance behaviour. The results suggest that agoraphobia defines more a particular type of anxiety disorder overlapping with panic disorder than merely a severe state of panic disorder.

Adult

Identification of minor affective disorders and implications for psychopharmacotherapy.

Five hundred general practice patients with functional complaints were studied with the Polydiagnostic Interview (PODI) to see whether DSM-IIIR criteria were able to specify affective disorders satisfactorily. Almost one third of the patients received the diagnosis of depression not otherwise specified (NOS). When Research Diagnostic Criteria were applied to these patients more than 70% received specific diagnoses. A modification of DSM-IIIR algorithms enabled us to further specify diagnoses in subjects with depression NOS. On the 17-item Hamilton Depression Scale many of these patients reached scores of 13 or more which is severe enough to justify a therapy trial with antidepressants.

Adjustment Disorders

A peripherally implanted permanent central venous access device.

Totally implanted central venous access devices provide reliable delivery of repetitive chemotherapy courses. However, placement of these ports requires special expertise and facilities, and is not without risk of major complications. This paper reports the technique of placing a new peripherally accessed, totally implantable, central venous port in 22 patients for the repeated administration of systemic chemotherapy. All ports were successfully placed under local anesthesia, with catheter tip location determined by an electronic sensor wand. The ports have been in use for a total of 387 patient-weeks. One port required removal secondary to an infection at the port site. Twenty-one ports have remained functional for infusion and blood sampling through 99 courses of chemotherapy. Acceptance by patients, nurses, and physicians has been excellent.

Antineoplastic Agents

Self- and observer assessment in anxiolytic drug trials: a comparison of their validity.

Self-rating scales are considered to be less useful for comparing different treatments in anxiety patients than observer-rating scales. However, the empirical evidence for this assumption is not adequate. A self-rating inventory of 35 items related to anxiety was perfectly parallel with an observer-rating inventory. Both instruments were used in the Cross National Collaborative Panic Study to compare the efficacy of imipramine, alprazolam and placebo in an 8-week drug trial in a sample of 1168 outpatients. The variance of the self-rating assessments was about two times higher. Both scales were equally sensitive to change; however, the measurement of change by means of the self-rating scale was slightly less consistent. The discriminative power of the observer-rating scale between placebo and active treatment was two to three times higher than that of the self-rating scale; consequently the observer-rating procedure provides a more valid instrument when the efficacies of different anxiolytic treatments are compared between different groups of patients.

Adult

Drug treatment of panic disorder: early response to treatment as a predictor of final outcome.

One of the core problems in clinical research is the detection of early changes in target symptoms that predict future therapeutic outcome. To analyze potential predictors of outcome, data of a multicenter study on patients with panic disorder were used. A total of 1010 patients were randomly allocated either to alprazolam, imipramine or placebo treatment. Early improvement in the number of spontaneous panic attacks within the first week of treatment predicted outcome exclusively in the alprazolam group. In contrast, placebo responders and nonresponders were differentiated by early changes in anticipatory anxiety intensity. For tricyclic antidepressants such as imipramine an evaluation period of more than one week is required to allow conclusions about outcome.

Adult

Failure of human immunodeficiency virus entry and infection in CD4-positive human brain and skin cells.

CD4 molecules on human cells function as a major receptor for human immunodeficiency virus (HIV); however, certain CD4-negative cell types may also be susceptible to infection. Therefore, we attempted to quantitate the relationship between HIV infection and CD4 expression on human cell lines before and after introduction of the CD4 gene by using a retrovirus vector. Prior to introduction of the CD4 expression vector, low levels of HIV infection were detected by a sensitive focal immunoassay on all three cell types studied. With several HIV strains in clones of human cervical carcinoma (HeLa) cells expressing different levels of CD4, HIV titer increased with increasing CD4 expression. In contrast, in squamous cell carcinoma cells (SCL1) and astroglial cells (U87MG), even high levels of CD4 expression failed to augment HIV infection. The CD4 protein expressed in these two cell lines had the expected molecular weight and was capable of binding HIV virions. However, in contrast to CD4-positive HeLa cells, CD4-positive U87MG and SCL1 cells were unable to form syncytia when cultured with cells expressing HIV envelope protein. Thus, the inability of HIV to infect these cells appeared to be due to lack of fusion between HIV virion envelope proteins and CD4-positive cell membranes. This block is infectivity was overcome when cells were infected with HIV which was pseudotyped with the envelope protein of amphotropic murine leukemia virus. Thus, in addition to CD4, other cell surface molecules appear to be required for successful HIV entry into and infection of these two human cell lines.

Astrocytoma

Normal and scrapie-associated forms of prion protein differ in their sensitivities to phospholipase and proteases in intact neuroblastoma cells.

Previous studies have indicated that scrapie infection results in the accumulation of a proteinase K-resistant form of an endogenous brain protein generally referred to as prion protein (PrP). The molecular nature of the scrapie-associated modification of PrP accounting for proteinase K resistance is not known. As an approach to understanding the cellular events associated with the PrP modification in brain tissue, we sought to identify proteinase K-resistant PrP (PrP-res) in scrapie-infected neuroblastoma cells in vitro and to compare properties of PrP-res with those of its normal proteinase K-sensitive homolog, PrP-sen. PrP-res was detected by immunoblot in scrapie-infected but not uninfected neuroblastoma clones. Densitometry of immunoblots indicated that there was two- to threefold more PrP-res than PrP-sen in one infected clone. Metabolic labeling and membrane immunofluorescence experiments indicated that PrP-sen was located on the cell surface and could be removed from intact cells by phosphatidylinositol-specific phospholipase C and proteases. In contrast, PrP-res was not removed after reaction with these enzymes. Thus, either the scrapie-associated PrP-res was not on the cell surface or it was there in a form that is resistant to these hydrolytic enzymes. Attempts to detect intracellular PrP-res by immunofluorescent staining of fixed and permeabilized cells revealed that PrP was present in discrete perinuclear Golgi-like structures. However, the staining pattern was similar in both scrapie-infected and uninfected clones, and thus the intracellular staining may have represented only PrP-sen. Analysis of scrapie infectivity in cells treated with extracellular phospholipase, proteinase K, and trypsin indicated that, like PrP-res, the scrapie agent was not removed from the infected cells by any of these enzymes.

Animals

[Panic attacks and avoidance behavior].

In a crossectional investigation based on a group of 122 patients with panic attacks, compiled from a variety of hospitals and therapy institutions, 97 patients were found to be suffering from panic disorder as a relevant medical problem. The disease, however, is often identified in an unsatisfactory manner. Avoidance behaviour (extensive or limited) associated with a severe form of panic disorder, was evident in more than one-half of the group (60%). In these patients the incidence of panic attacks is higher, anxiety is more marked, and there are more often additional anxiety disorders (generalised anxiety, sociophobia). These results underline the importance of early recognition and specific treatment of panic disorder to prevent development of avoidance behaviour.

Adult